package thinkingInJava.io;
// page 526 用内部类实现 DirList
//: io/DirList2.java
//Uses anonymous inner classes.
//{Args: "D.*\.java"}
import java.util.regex.*;
import java.io.*;
import java.util.*;

public class DirList2 {
public static FilenameFilter filter(final String regex) { // 内部类传入参数必须 final
 // Creation of anonymous inner class:
 return new FilenameFilter() {
   private Pattern pattern = Pattern.compile(regex);
   public boolean accept(File dir, String name) {
     return pattern.matcher(name).matches();
   }
 }; // End of anonymous inner class
}
public static void main(String[] args) {
 File path = new File(".");
 String[] list;
 if(args.length == 0)
   list = path.list();
 else
   list = path.list(filter(args[0]));
 Arrays.sort(list, String.CASE_INSENSITIVE_ORDER);
 for(String dirItem : list)
   System.out.println(dirItem);
}
} /* Output:
DirectoryDemo.java
DirList.java
DirList2.java
DirList3.java
*///:~

